When an extension cord, power strip or similar electrical power supply device is used there is frequently an issue as to whether the electrical power supply device is operatively connected to power. Similarly, when a load is either remote from the end of the power supply device at which the operator is located, or where the power-consuming load is silent, such as a car's block heater or battery charger, there is an issue as to whether the power-consuming device is properly attached and drawing current.
What is needed is a inexpensive and reliable way for the operator to determine if the power supply device is attached to an operative power supply and if the load is operative and drawing current.